Virology Quiz on Virus Classification

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which virus is classified under the hepevirus genus?

Norwalk virus

Hepatitis C virus

Hepatitis E virus (correct)

Rotavirus

What type of RNA does the rotavirus contain?

Cyclic RNA

Linear RNA

Single-stranded RNA

Double-stranded RNA (correct)

Which of the following groups includes the rubella virus?

Flaviviruses

Togaviruses (correct)

Reoviruses

Alphaviruses

How many segments of RNA are present in the influenza virus?

8 Signup and view all the answers

What distinguishes retroviruses from other viruses?

Reverse transcription of RNA to DNA Signup and view all the answers

What type of genome do paramyxoviruses have?

Single-stranded, linear, negative-polarity RNA Signup and view all the answers

Which of the following is NOT a virus included in the flavivirus group?

Rubella virus Signup and view all the answers

Which pathogen primarily causes diarrhea in infants?

Rotavirus Signup and view all the answers

What type of viral genome is capable of being used directly as a template for protein synthesis?

Positive-strand RNA Signup and view all the answers

Which geometric configuration is NOT typically associated with viral capsid symmetry?

Cubic Signup and view all the answers

What does the term 'nucleocapsid' refer to?

The complex of genome and capsid proteins Signup and view all the answers

What type of symmetry is characterized by capsids built from a limited number of different polypeptides?

Icosahedral symmetry Signup and view all the answers

Which type of single-stranded RNA cannot be directly used as messenger RNA for protein synthesis?

Negative-strand RNA Signup and view all the answers

In viruses with helical symmetry, what bonds protomer units together?

Hydrogen bonds Signup and view all the answers

Which of the following correctly describes capsomers?

Structural subassemblies in icosahedral capsids Signup and view all the answers

What is the most common form of viral genome found in nature?

ssRNA and dsDNA Signup and view all the answers

Which viruses are known for causing latent infections?

Herpesviruses Signup and view all the answers

What distinguishes Hepadnaviruses from other virus families?

Their complete strand is not a covalently closed circle. Signup and view all the answers

Which of the following viruses is a known human pathogen from the Herpesvirus family?

Epstein-Barr virus Signup and view all the answers

Poxviruses are associated with which of the following characteristics?

Bricklike shape with complex capsid symmetry Signup and view all the answers

Which group includes the smallest RNA viruses?

Picornaviruses Signup and view all the answers

What type of genetic material do caliciviruses possess?

Single-stranded linear RNA Signup and view all the answers

Which virus family is responsible for pharyngitis and respiratory tract diseases?

Adenoviruses Signup and view all the answers

Which virus is notably used in the smallpox vaccine?

Vaccinia virus Signup and view all the answers

What characterizes a virus that is referred to as 'naked'?

It lacks a lipid-containing membrane. Signup and view all the answers

What is the mode of transmission for MERS to humans?

Close contact with camels Signup and view all the answers

Which of the following is true about enveloped viruses?

The envelope is derived from host cell membranes. Signup and view all the answers

Which virus strain is responsible for COVID-19?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Signup and view all the answers

What percentage of people typically recover from COVID-19 without special treatment?

80% Signup and view all the answers

What is the purpose of the proteins that replace cellular membrane proteins in enveloped viruses?

To provide virus-specific antigenicity. Signup and view all the answers

What is a common symptom that may develop in some COVID-19 patients?

Loss of taste and smell Signup and view all the answers

In the Baltimore classification, which group contains viruses with single-stranded RNA that acts as a template for replication?

Group VI Signup and view all the answers

When was COVID-19 declared a pandemic by WHO?

March 2020 Signup and view all the answers

Which of the following viral families are classified as nonenveloped and icosahedral?

Adenoviruses and parvoviruses Signup and view all the answers

The acronym 'papova' in papovaviruses stands for which of the following viruses?

Papilloma, polyoma, and simian vacuolating viruses. Signup and view all the answers

What underlying conditions increase the risk of serious illness from COVID-19?

High blood pressure and diabetes Signup and view all the answers

During what incubation period does COVID-19 generally develop symptoms?

1-14 days Signup and view all the answers

What is a key characteristic of poxviruses within their classification?

They are the largest viruses and exhibit complex internal symmetry. Signup and view all the answers

What was the primary geographical location where COVID-19 was first identified?

Wuhan, China Signup and view all the answers

Which of the following viruses is categorized as a dsDNA virus according to the Baltimore classification?

Hepatitis B virus Signup and view all the answers

Which of the following vaccines is classified as an mRNA vaccine?

Pfizer-BioNTech COVID-19 vaccine Signup and view all the answers

What type of virus is the Sinovac vaccine based on?

Inactivated virus Signup and view all the answers

What is the genomic composition of parvoviruses?

Single-stranded DNA Signup and view all the answers

Which of the following families of RNA viruses have segmented RNA?

Reoviruses Signup and view all the answers

Which of these viruses is classified as a double-stranded RNA virus?

Reovirus Signup and view all the answers

Which of the following statements about DNA viruses is true?

Adenoviruses are naked nucleocapsid viruses. Signup and view all the answers

What is the classification of the Oxford AstraZeneca vaccine?

Viral vector Signup and view all the answers

Positive-polarity RNA viruses include which of the following?

Coronaviruses Signup and view all the answers

Study Notes

Medical Important Viruses

Viruses are infectious agents made up of a genome (RNA or DNA) and a protein coat (capsid).
Some viruses have an additional lipid bilayer envelope.
A complete virus particle is called a virion.
Viruses replicate inside host cells, using the host's machinery.
The process depends on viral structural and functional characteristics.
Viral replication can vary between viral species.
Viruses range in size, from 20nm (parvoviruses) to 300nm (poxviruses).
Viruses are much smaller than cells.
Viruses are classified by different factors, including viral nucleic acid type, replication strategy, capsid symmetry, and the presence/absence of an envelope. This results in naming and categorising viruses into families, subfamilies, genera, and species.
Viruses use specific mechanisms to enter cells and exploit host cells for replication and production of new viral virions.
Different viruses have varied structures, hence they pose different challenges to human, animal, and plant health.
Viruses often have unique characteristics to facilitate their interactions with specific host cells, resulting in particular diseases in the various hosts they infect.
The structure of the capsid, the protein component, can determine how the virus is structured. This in turn defines the type of replication.

Virus Structure

Viruses have a core containing nucleic acid (DNA or RNA).
Viruses may or may not have an envelope surrounding the protein coat.
The protein coat (capsid) protects the viral genome.
The overall capsid structure (helical or icosahedral) is important for viral classification. The capsids are made of multiple copies of a single polypeptide, hence saving genetic information in the virus.
Viruses can be naked or enveloped.

Viral Genome

Viruses can have DNA or RNA.
Single-stranded (ss) or double-stranded(ds)
RNA viruses can be positive or negative polarity
Positive polarity can be used to synthesize proteins directly.
Negative polarity needs to be converted to a positive template before protein synthesis can occur.
Viral genome is critical to the overall function of the virus as each particular virus has its own genome to follow and ensure functionality.

Viral Replication

Viruses depend on host cells for replication.
Viral replication steps include attachment, penetration, uncoating, gene expression and replication, assembly, and release.
The viral genome can also be used to develop vaccines.
Different types of viruses replicate differently, e.g. viruses that replicate in the nucleus vs viruses that replicate in the cytoplasm, depending on the type of virus, the host the virus infects and the location of the viral replication.

Types of Viruses

Herpesviruses, adenoviruses, parvoviruses, poxviruses
Picornaviruses, caliciviruses, reoviruses, coronaviruses, flaviviruses, togaviruses, retroviruses, rhabdoviruses, filoviruses.

Baltimore Classification

The Baltimore classification system groups viruses primarily based on their genome type and the mechanism used in the transcription of the viral genetic material.
There are 7 groups (I to VII). Each group has its own defining characteristics to ensure the system gives the most accurate classification of viruses and the mechanisms of disease.

Viral Replication Cycles

The viral replication cycle describes the processes that allow viruses to multiply or replicate and generate new virions.
Viral replication cycles are specific to the type of virus present and how they infect different hosts.
The steps of infection are often specific to each virus present, ensuring that the cell is not harmed.

Medical Significance of Viruses

Several medically important viral infections have been discovered and studied from a medical and biological point of view.
Various viruses can cause significant diseases in humans, animals, and plants.
Viruses can have complex interactions with the cells they infect.

Viral Diseases

Specific diseases are caused by viruses.
Examples include the common cold, influenza, COVID-19, measles, and HIV.
Viruses cause a wide spectrum of diseases and can produce very unique symptoms.

COVID-19 (SARS-CoV-2)

The pandemic and emerging disease with new strains and mutations
Caused respiratory illness.
Originated in Wuhan, China
Spread globally through infection
Common symptoms are fever, tiredness, and dry cough.
Some people experience more serious symptoms.
Vaccination efforts were a response to the health crisis

Viral Symptoms

Symptoms vary by virus.
Symptoms often include fever, cough, and sometimes other symptoms (depending on type of virus and disease).

Viral Transmission

Respiratory, fecal-oral, or bloodborne.
Different transmission methods are employed by different viruses.
The route of transmission is crucial in understanding how to stop the spread of the infection and preventing it from infecting others.

Viral Vaccines

Used to prevent viral infections.
Examples include the COVID-19 vaccines.

Prevention

Handwashing, avoiding contact with sick individuals, and wearing masks can lead to a reduction of cases and transmission of viruses.

Molecular Tests

Nucleic acid detection.
Antibody tests are two common types of viral detection.

Relevant Statistics

17 times more likely unvaccinated people are hospitalized.

Viral Variants

Different strains of viruses evolve, which makes it difficult to develop effective treatments and/or vaccines.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on various viruses, their classifications, and genetic structures. This quiz will challenge you on topics such as hepeviruses, rotaviruses, and retroviruses, among others. Perfect for students and enthusiasts of virology and microbiology.